Regulatory Actions

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Final Revisions to Nitrogen and Sulfur Oxides Secondary National Air Quality Standards
March 20, 2012 - After a careful review of the best available science, the EPA took action to retain the current secondary ambient air quality standards for oxides of nitrogen (NOx) and oxides of sulfur (SOx) . This same action is also posted on the website for nitrogen dioxide regulatory actions.

Secondary National Ambient Air Quality Standards for Oxides of Nitrogen and Oxides of Sulfur - Public Hearing
EPA will hold a public hearing to take comment on its proposal to retain and revise the secondary National Ambient Air Quality Standards for oxides of nitrogen and oxides of sulfur. The hearing will be held on Thursday, August 25, 2011 in Arlington, VA at:

Each speaker will have 5 minutes to present testimony. Please contact Ms. Sherry Russell prior to the public hearing at e-mail russell.sherry@epa.gov or telephone (919-541-0306) to pre-register to speak at the hearing and/or if you will need specific audiovisual (AV) equipment or translation services (for non-English speaking commenters). This should be done no later than 5 pm on August 23, 2011.

The public hearing will begin at 10 a.m. and continue until 7 p.m. or later, if necessary, depending on the number of speakers wishing to participate. The EPA will make every effort to accommodate all speakers that arrive and register before 7 p.m. There will be a break between 1:00 and 2:30 PM for lunch.

Security: All visitors will be required to show a valid picture ID upon entering the building. You will also have to sign in and go through a security screening. Any electronic equipment you bring will also need to be registered.

Proposed Revisions to Nitrogen and Sulfur Oxides Secondary National Air Quality Standards
July 12, 2011 – After a careful review of the best available science, the EPA is proposing changes in secondary air quality standards for nitrogen oxides (NOx) and sulfur oxides (SOx) to better protect sensitive lakes and streams. This same action is also posted on the website for sulfur dioxide regulatory actions.

Final Revisions to Sulfur Dioxide Primary National Air Quality Standard
June 2, 2010 - The Environmental Protection Agency strengthened the National Ambient Air Quality Standard for sulfur dioxide. The new 1-hour standard applies only to the primary standard set to protect public health.

Proposed Revisions to Sulfur Dioxide Primary National Air Quality Standard
November 16, 2009 - The Environmental Protection Agency has proposed revisions to the National Ambient Air Quality Standard for sulfur dioxide. This revision would apply only to the primary standard set to protect public health.